The present invention concerns the shielding of magnetic pulses generated by a flyback transformer in a visual display terminal.
Within a typical cathode ray tube terminal there are three main sources of magnetic fields. The flyback transformer is the largest source of magnetic fields, followed by the deflection yoke and the width and linearity coils.
In the prior art various methods have been used to shield the magnetic fields. For example, deflection yoke stray magnetic fields have been cancelled by attaching additional windings to the yoke. Current through these windings create an equal but opposite magnetic field to the undesired stray magnetic fields. Also metal shields have been placed around the flyback transformer. These metal shields have made of a single layer of metal or two concentric layers of metal separated by an insulating layer.